Shade throwing would be justified in my opinion. "E-reader" isn't normally used to describe tablets. The light profile of a dynamic LED screen is probably very different from the ambient steady backlight on a Kindle.
Or even a Kobo (at least my old one) where the light is under the frame at the top, and projects down onto the screen so you're getting reflected light similar to an external source.
Kindles have a backlight? Then I expect it to be LED as well. I'm not sure then you can be so dismissive of a back-lit Kindle and its effect on evening reading.
They have a frontlight rather than a backlight. And there's quite a bit of evidence that colour temperature and brightness both have a big effect. But I broadly agree that it will still have an effect. I use my kindle without the backlight and with a warm coloured lamp.
I'm not dismissing it having an effect. But isn't it probable that the light profile would be somewhat different for an actual monitor and a back/sidelit eInk dislay? If so, the effect may differ as well.
Front light, I agree, would probably have a different spectral profile.
Technically it’s a front-light, shining on the front of the screen from the side. But the nature of the eInk is such that you don’t have to use the built in light, you could just turn in your normal lamp.